Sand and/or Gravel As a Medium?

Not that I'm considering doing it, but I sometimes get curious about how good a medium coarse sand would make. Seems to me that it would drain well, be easy to flush, and be a difficult medium for pests and bacteria to establish themselves in. Has anyone ever tried it? What am I missing here?

does not hold water well but might be an interesting experiment in hydroponics.

Yeah, that was what I was thinking - as a hydroponic medium. You could flood several times a day, and it would stay damp but still drain well. It's totally non-porous, so you could make instant adjustments to your nutrient mix on a daily basis if need be. I'm really curious how that would work out. Seems someone must have tried it at some point, but I've never heard of it.

base soil mix:
sand or gravel + compost + vermicastings + peat ( or coco, biochar, leaf mould, etc)

it's a good draining component but not great alone since it compacts and eventually will repel water

Yeah, that's a good point - water does compact most grades of sand. But I wonder if fine to very fine gravel (particle size of 4 to 8 mm) might be an effective hydroponic medium. I think I may give it a try sometime, just to see.

Don't get me wrong, I still love my coco and always will. Not going to give up on that. I've just become really curious about whether sand or gravel could be an effective hydroponic medium, and now that the idea has taken root, I can't get it out of my head. I'm really curious to see how it would work. It seems to me it could be used much like hydroton - but being non-porous, it would basically be inert, and you'd have no problems with salt buildup or pests like fungus gnats.

People use to use 3/8 inch pea gravel for ebb and flow systems, back in the days before expanded clay pellets hit the market. I personally never tried it but I heard it worked great as long as you didn't have to move it around. Super heavy stuff and moving it around can crush your roots.

I think sand was the very first medium used in hydro..


Cool info here about sand in Hydro http://www.hydroponics.com.au/issue-02-sand-culture/

I always throw a big handful of gardening/horticultural sand in my peat mix along with vermiculite and perlite.
Don't use Builders sand!

Also there is the weight of the gravel to consider..

i used both in my hydro with success. The only issue I had with each was weight, sand clogging/res/pump etc. drain to waste was an option, would have been better for me, but I couldnt bring myself to throw away ferts after one rinse in a sand bag/////

Lucky Luke said:

I think sand was the very first medium used in hydro..


Cool info here about sand in Hydro http://www.hydroponics.com.au/issue-02-sand-culture/

Click to expand...

I think water was the first, mayan/aztec maybe, dipping trays on timers into fish ponds......I dont really know though, elders dont share much these days

Skunk Baxter said:

Yeah, that was what I was thinking - as a hydroponic medium. You could flood several times a day, and it would stay damp but still drain well. It's totally non-porous, so you could make instant adjustments to your nutrient mix on a daily basis if need be. I'm really curious how that would work out. Seems someone must have tried it at some point, but I've never heard of it.

Click to expand...

I honed my hydro medium over several years, going from rock wool> hydroton> lava rock> and finally, I found polished ornamental stones invaluable (Dollar Store). It is easy to clean, leaves air gaps for roots to grow into an slurp between floods AND super easy to separate from the roots/clean and reuse